1. Field of the Invention
The invention relates to a comfort liner arranged inside the upper of a boot, such as a sports boot, and concerns a liner that includes an envelope made in one single piece to fit the foot and the lower leg of the user.
2. Description of Background and Relevant Information
Known liners of the aforementioned type are generally provided with an opening for the introduction of the foot, closed by flaps or by a tongue.
Patents FR 2 368 239, EP 066 133, Patent Applications FR 2 742 969 and DE 41 29 270, describe such liners and they are cited as examples.
More specifically, Patent FR 2 368 239 concerns a liner with lateral slits in the zone covering the lower leg of the user. This liner is molded in the open position such that at rest it is always open ready for putting on and taking off. This predisposition to opening given to the liner actually does facilitate putting on and taking off but presents the drawback of opening the boot upper very wide as soon as the closing devices thereof are released. In effect, when the liner returns elastically to its open position, it simultaneously pushes the flaps of the boot upper toward the outside, which significantly increases the volume thereof, making it inconvenient to walk or simply to store it. Another drawback concerns retaining the foot in the liner and in the boot per se.
In effect, because the liner does not have its own tightening means, it is the deformation and/or the displacement imposed on the upper, by means of the closing devices thereof, which produces the coming together of the envelope of the liner on the foot. Taking into account the relative flexibility of the upper and the one-piece structure of the envelope of the liner, an approximate adjustment to the foot results, leaving numerous empty spaces, particularly outside the protruding parts of the foot. These absences of contact in the enclosure of the foot consequently deprive the user of tactile sensations and reduce the retention of the liner in the boot.
This is also what is found in the liner described in Patent EP 066 133 despite the fact that it is not molded in the open position and despite the use of a tightening device on the opening for the introduction of the foot. In effect, the tightening device is located in the area of the lower leg and has no effect of retention and/or adjustment on the foot which is simply slipped into the bottom part of the envelope of the liner. In fact, there is only a small rear tongue which is supposed to contribute to the adaptation of the envelope of the liner around the ankle. Moreover, since the position of this tongue is subject to that of the back part of the boot upper, it relies, as in the example of the preceding liner, on the deformation and/or the movement imposed on the upper to produce the relative coming together of the envelope of the liner on the foot. Consequently, there results an adjustment of the liner on the foot which remains approximate because only the heel is nested by the rear tongue and that only when the boot upper is closed.
In the example of the liner disclosed in Patent Application FR 2 742 969, this drawback relative to the adjustment of the envelope of the liner to the foot is at least partially resolved due to the use of a very low resistance material for the envelope and a plurality of tightening straps which cover this envelope with a certain mobility from a retention means.
More specifically, the use of a plurality of straps thus mounted on the outside of the envelope of the liner, from the zone of the lower leg to the foot, enables adjustment of the liner precisely at the point where each strap extends without deteriorating the envelope thereof despite the low resistance of the material which constitutes it. In effect, because of the fact that it is on the ends of each strap that the tightening force is exerted and that each strap is movable relative to the envelope of the liner from its retention means, the envelope of the liner is not subject to any traction but essentially to compression of its wall between the strap and the zone of the foot and/or of the lower leg opposite it.
Due to its various arrangements, the envelope of the liner can be adjusted on the foot and/or the lower leg of the user by means of a tightening device, for example, a lace, ensuring close and continuous contact. However, given that the envelope is made of a low-resistance material, a very poor distribution of pressures is produced, which are notably high at the location of each strap and clearly lower between two straps.
Moreover, given that the straps are movable relative to the envelope of the liner, i.e., free to slip relative thereto in the direction of tightening and loosening, their ends connected to the tightening device tend to move out of alignment along the opening for the insertion of the foot into the liner with each putting on and taking off. The user of the liner is consequently always forced to realign or to check the position of the ends of the straps before proceeding with the adjustment of the envelope on the foot by means of the tightening device.
In the case of the liner described in the Patent Application DE 41 29 270, this problem of disalignment obviously does not occur because the tightening means consist of a traction tie which is totally guided over an elastically deformable tightening zone and situated in the top part of the envelope of the liner in correspondence with the instep girth of the user.
More specifically, in this type of liner, the traction tie tightens the envelope on the instep girth and simultaneously pushes the heel into the rear part of the envelope of the liner by pulling on a strap immovably attached thereto. This arrangement enables adjusting the liner relatively well on the foot but has the drawback of implementing a system of guidance of the tie which is complex and has relatively rigid components. Moreover, this system takes space in the zone of the instep girth, which necessitates providing a larger volume for the boot upper.
Also, the tightening of the boot upper over the liner becomes problematic because any pressure on one of the rigid components of the guidance system is likely to generate a painful point of contact on the foot of the user.
An object of the present invention is to overcome the aforementioned various problems and drawbacks.
A primary object of the invention is to enable continuous adjustment of the envelope of the liner both on the foot, with heel locking, and on the lower leg of the user, as well as good distribution of the pressures and/or the tightening forces, without the boot upper and/or a tightening-closing device thereof being involved.
Another object is to give the user the possibility of acting to tighten and loosen the liner by means of its own adjustment device and whose control is accessible from the outside of the boot upper, whether it is open or closed.
The invention also provides for ensuring retention in constant position of the means of tightening the adjustment device on the envelope of the liner along the opening for the insertion of the foot, whether the device is in the active or inactive position.
Yet another object of the invention is to enable obtaining the boot upper in a shape adjusted as close as possible to the envelope of the liner, thus the least voluminous possible, without this being capable of generating painful points of contact on the foot and/or the lower leg.
To obtain these objects, the liner adapted to be arranged inside the upper of a boot has an envelope produced in a single piece to, cover the foot and the lower leg of the user, and which is provided with an upwardly directed oppening for the introduction of the foot. The opening is a slit which, extends along one side of the liner envelope. This slit is demarcated by a pair of overlapping flaps which are subject to a lace and lock adjustment device, whose control is accessible from the outside of the boot upper, and a plurality of fabric keepers, each attached to the envelope in proximity to and on either side of the slit to ensure the guidance of the lace.
Also, a tightening strap has one end attached to the side of the liner envelope opposite that where the slit extends, and it freely surrounds the rear part of the envelope approximately above the zone corresponding to the heel and is then connected by its free end and in the manner of a keeper to the lace of the adjustment device in proximity to the slit which forms the opening for the introduction of the foot.
These different characteristics enable obtaining the aforementioned objects. In effect, they give the liner its own means of tightening and adjustment on the foot and the lower leg of the user, which avoids involving the boot upper and/or a tightening-closing device thereof. Conversely, they enable the action of tightening and loosening the liner without taking into account the open and/or closed position of the boot upper.
Furthermore, the arrangement of the opening for the introduction of the foot on one side of the envelope of the liner and the attachment of each keeper in proximity to and on either side of the slit constituting this opening avoids having to use means or components of the adjustment device on the front part of the envelope of the liner. Consequently, the boot upper may be adjusted to the shape of the envelope of the liner without risking creating painful points of contact on the foot and/or the lower leg, all the more so since the keepers are flattened rings and thus protrude very little.
Moreover, given that each keeper is attached in proximity to the slit, the risks of disalignment of the guidance system of the lace are avoided, in particular when the latter is completely loosened. In fact, the tightening means of the adjustment device are maintained in a constant position on the envelope of the liner, whether the adjustment device is in the active or inactive position.
Also, the demarcating of the slit by a pair of overlapping flaps enables adjusting the envelope of the liner on the foot and the lower leg of the user by simply varying the overlap value of the flaps. This operation requires applying traction to the wall of the envelope of the liner to cause a modification of the inside volume of the envelope but has the advantage of distributing pressures over the entire envelope.
Additionally, the connection of the free end of the tightening strap implemented above the zone corresponding to the heel with the lace of the adjustment device makes it possible to more specifically nest the heel simultaneously with the adjustment of the liner envelope on the foot and the lower leg. In effect, since the tightening strap is free relative to the wall of the envelope which it overlaps above the heel and thus capable of sliding relative thereto, applying tension to it enables pushing back and/or compressing the wall of the envelope in direction despite the highly curved shape thereof at this heel level.
According to one embodiment, the envelope is provided, on its outside wall, with reinforcement yokes on which the keepers of the lace adjustment device are at least partially attached.
Advantageously, a yoke extends above and/or over the zone corresponding to the heel at the area where the tightening strap passes, and a keeper is provided on this yoke to maintain and guide the free end of the strap to the lace of the adjustment device in proximity to the slit forming the opening for the introduction of the foot.
According to a preferred embodiment, the slit extends on only one side of the liner from the top part of the envelope thereof where it opens, to the bottom front part where it covers the foot of the user, and an elastic strip is attached on either side of the slit in this bottom front part.
Additionally, a flexible, elastic material is advantageously used in the zone between the bottom and top front parts of the envelope. More specifically, this material constituting the wall of the envelope is placed above the bottom front part of the envelope substantially in correspondence with the zone of the flexion fold of the foot of the user. With this arrangement, the formation of improper folds which interfere with the adjustment and retention of the envelope on the foot is avoided.